tl;dr inbound
He's mentioned Gray Goose vodka in some of our conversations, and Gamerfood has brought it up as well. That's about all I know though, for an alcoholic he doesn't talk about it a lot, which is odd because Jace seems to boast about everything that he thinks will make him appear "edgy"; at least, he doesn't boast about it NEARLY as much as he boast about drugs, which leads me to believe he's hiding something, or realizes that his problems with it outweigh the validation he'll get from bragging about it to his dipshit friends.
I think we're both aware of the fake Jack Daniels tequila bottle in his earlier videos, which was pretty hilarious and yet another pathetic example of him trying to look like a badass and failing miserably. For a while that made me think the entire "alcoholic" thing was made up, like any other persona of his, because he thought it would make him look like a badass. Then I saw the VLOG-ust video of him bitching about AA though and he seemed genuinely distressed about it, and I don't think if the entire thing was invented that he would have a realistic way of how bad alcoholism actually is; if he's going to invent a fantasy persona, it's going to be perfect, with no flaws, because he's a total narcissist... and plus, there's not much value in escapism if you're escaping to a situation worse than the real one.
I still am not sure about it to this day, whether it's just another bullshit persona of his designed to appear cool, or edgy, or garner sympathy or whatever... or whether it's an actual problem that he has, but I'm leaning towards it being real because he doesn't talk/brag about it as much as I would expect if it was made up. Sadly, there's still a lot of gaps in our information about Jace's life.
Regardless of the substance though, the problem with Jace is that, even while high, he seems to have no filter and no problem multi-tasking or doing things he really shouldn't. Most people when under the influence understand that they're impaired and have a sense of caution; Jace sees no problem whatsoever with driving while high, for example, and even touts it as "cool" on twitter. Likewise, he saw nothing wrong with filming himself rambling incoherently in the midst of an adderall tailspin and then posting it publicly - so much that he still hasn't taken down the video today, despite the fact that it makes him look like a pre-columbine paranoid schizo.
Of course, there's also the escapism, which I believe to be the primary draw. Jace has a really addictive personality and he's going to find escapism for himself no matter what, whether it's through video games, alcohol, weed, harder drugs, his shitty book, his Deagle Nation "missions", his vlogs, his "FACT ZONE" fantasy of being a hit newscaster... whatever it might be, Jace's life is designed around escapism. Even if he goes completely sober (which I doubt) he will still have the same problems until he attacks the root cause which is that he is running away from his own problems.